NEW YORK (Reuters) - A couple visiting from New Mexico are believed to have contracted bubonic plague and if confirmed this would constitute the first case of the illness in New York City in more than 100 years, health officials said on Wednesday.

The two are "being evaluated for plague," Health Commissioner Thomas Frieden told a news conference. The male patient, 53, is a presumptive positive for the illness and is in critical condition, he said. The female patient, 47, is in stable condition, officials said.